One of the most persistent and annoying problems facing users of hearing aids is feedback, which is perceived by the user as a high pitched high volume whistling in the ear. Feedback can be a problem with behind-the-ear hearing aids but is particularly prevelant with in-the-ear hearing aids where the microphone and the speaker are in relatively close proximity. Various approaches to solving the feedback problem have been taken, including electronic filter circuits, peak control circuits (U.S. Pat. No. 4,689,818), adaptive noise suppressors (U. S. Pat. No. 4,658,426), microprocessor controlled hearing aids (U.S. Pat. No. 4,596,902), clipping circuits (U.S. Pat. No. 4,506,113), notch filters (U.S. Pat. No. 4,232,192) and other amplifier related circuits. Each of these electronic approaches results in a more complicated hearing aid design and increased cost. Various mechanical approaches have also been taken such as earmolds and hollow cylinder gaskets. Earmolds must be custom fitted to each user's uniquely shaped ears, are quite expensive and can require multiple visits to a doctor's office before a satisfactory fit is achieved. Gaskets and O-rings tend to slide off the narrow end of the hearing aid when the hearing aid is removed from the ear. This tendency is exacerbated by perspiration, ear wax or other lubricants that find their way between the hearing aid and the gasket or O-ring. An O-ring or gasket that slips off can easily get lost or even worse can pose a serious medical problem if it gets trapped or lost inside the ear canal. U.S. Pat. No. 2,521,414 to Schier shows an insert intended to be placed over the tip of a hearing aid for placement within the ear canal, and U. S. Pat. No. 3,080,011 shows an insert to be placed over the tip of the tube of a behind the ear hearing aid.